/* Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.activiti.engine.impl.db;

import org.activiti.engine.impl.cfg.IdGenerator;
import org.activiti.engine.impl.cmd.GetNextIdBlockCmd;
import org.activiti.engine.impl.interceptor.CommandConfig;
import org.activiti.engine.impl.interceptor.CommandExecutor;

/**
 * @author Tom Baeyens
 */
public class DbIdGenerator implements IdGenerator {

    protected int idBlockSize;
    protected long nextId;
    protected long lastId = -1;

    protected CommandExecutor commandExecutor;
    protected CommandConfig commandConfig;

    @Override
    public synchronized String getNextId() {
        if (lastId < nextId) {
            getNewBlock();
        }
        long _nextId = nextId++;
        return Long.toString(_nextId);
    }

    protected synchronized void getNewBlock() {
        IdBlock idBlock = commandExecutor.execute(commandConfig, new GetNextIdBlockCmd(idBlockSize));
        this.nextId = idBlock.getNextId();
        this.lastId = idBlock.getLastId();
    }

    public int getIdBlockSize() {
        return idBlockSize;
    }

    public void setIdBlockSize(int idBlockSize) {
        this.idBlockSize = idBlockSize;
    }

    public CommandExecutor getCommandExecutor() {
        return commandExecutor;
    }

    public void setCommandExecutor(CommandExecutor commandExecutor) {
        this.commandExecutor = commandExecutor;
    }

    public CommandConfig getCommandConfig() {
        return commandConfig;
    }

    public void setCommandConfig(CommandConfig commandConfig) {
        this.commandConfig = commandConfig;
    }
}
